One of the worries about fracking is the humongous huge amount of water it takes to frack a well. Around *4,000,000 gallons* for just one well. That’s more than I could drink in a lifetime.

Let’s put that in perspective. I mentioned this before here, but let’s take another look.

The Garrison dam at the end of Lake Sakakawea provides hydroelectric power. You can get some background info here.

Bruce Oksol provides some background at his post *Water For Fracking In the Bakken*.

His conclusion?

Less than a day’s worth of discharge from the Garrison Dam should be enough water to frack all the wells that will be fracked in the North Dakota Bakken this year.

I’ll backstop his calculations below, which confirm his calculation.

Daily discharge for May 25 through May 28 is 20,500 cubic feet per second.

Cool.

As he points out, a cubic foot of liquid equals 7 gallons.

So here we go:

- 20,500 cubic feet per second
- 143,500 gallons per second
- 8,610,000 gallons per minute
- 516.6 million gallons per hour
- 12.398 billion gallons per day

Lets look at usage.

As I mentioned in this post, a report in Dickinson Press here says last year 5.4 billion gallons were used for drilling.

So in terms of daily discharge from Garrison dam, that would be 12.398 billion gallons discharge per day divided by 5.4B gallons per year for drilling times 24 hours a day = 10.4 hours of discharge.

So ** less than one half day **of the discharge from the dam would be enough water to drill all the wells last year.

Let’s try another direction.

Per well use is around 4M barrels times estimated 2,000 wells this year equals 8B gallons. That would be 15.5 hours (12.398B / 8B * 24).

That would be * about 2/3rds of a days *discharge.

So somewhere between a half day and two-thirds of a day discharge.

Lets go from another angle.

The discharge report from the Corps of Engineers is 20,500 cfs for the four-day period from 0000 hours 5-25 through 2400 hours 5-28.

For four days, that will be 49.6 billion gallons (12.39B x 24). Let’s use last year’s estimated usage of 5.4 billion gallons for drilling.

That means in the 4 day reporting period, the water discharged downstream into the Missouri river will be equal to what would be used in just over** 9 years of drilling** at last year’s production rate (12.398 x 4 / 5.4 = 9.18 years). Four days discharge is equal to nine years usage.

Looks to me like there is plenty of water.